The ionic species created by the O(2)-plasma treatment of poly(styrene) surfaces are able to initiate the polymerization of glycidol in the absence of any initiator. Consequently, thin hydrophilic films of poly(glycidol) are formed at the surface of oxygen plasma-treated polymer surfaces upon treatment with glycidol. These were characterized with the aid of X-ray photoelectron spectrometry, contact angle measurements, and scanning electron microscopy. A significant decrease of unspecific protein adsorption at the plasma-treated glycidol-modified surfaces was evidenced using fluorescence microscopy. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 25432550, 2011